1. Field of the Invention
The present invention relates to self-latching hinges, and particularly to such a hinge wherein the latching force is provided by the resilience of one of the hinge leaves.
2. Description of the Prior Art
Self-latching hinges have gained widespread acceptance in the building industry for installation of cabinet doors and the like. Such hinges include a force providing mechanism which maintains the cabinet door closed without the need for a separate latch. Use of self-latching hinges eliminates both the cost of the latch hardware and the even greater expense of latch installation.
In typical prior art self-latching hinges, a spring biased roller or wedge incorporated in one hinge leaf presses against a notched hinge pin bearing sleeve on the other leaf. As the hinge members are rotated toward the door-closing position, the roller or wedge is biased against the bearing sleeve notch to force the hinge closed. Some effort is required to open the hinge against the biasing force.
In most self-latching hinges of the type described, the roller or wedge biasing force is provided by a separate spring element mounted to one hinge leaf. Assembly is difficult, and both hinge leaves must be formed of relatively thick metal to withstand the substantial spring force. One object of the present invention is to provide a self-latching hinge requiring no separate spring element. A unitary hinge member functions both as a hinge leaf and as the force providing element for releasably maintaining the hinge closed. Another object is to provide a self-latching hinge wherein one hinge leaf is formed of a resilient material, typically a plastic which may be less costly than metal. This enables use of inexpensive molding techniques to fabricate the hinge leaf.
Yet shortcoming of prior art self-latching hinges concerned the manner of attachment to the frame or closure. Most commonly, one of the metal hinge leaves was fastened by screws to the cabinet or door frame. By providing a hinge wherein one leaf is formed of plastic, alternative means for attachment are available. Thus another object of the present invention is to provide a hinge construction wherein one leaf may be formed integral with a closure frame, or may be attached in other unique ways.